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Low field magnetotransport in strained Si/SiGe cavities

G. Scappucci·L. Di Gaspare·F. Evangelisti·E. Giovine·A. Notargiacomo·R. Leoni·V. Piazza·P. Pingue·F. Beltram
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Abstract

Low field magnetotransport revealing signatures of ballistic transport effects in strained Si/SiGe cavities is investigated. We fabricated strained Si/SiGe cavities by confining a high mobility Si/SiGe 2DEG in a bended nanowire geometry defined by electron-beam lithography and reactive ion etching. The main features observed in the low temperature magnetoresistance curves are the presence of a zero-field magnetoresistance peak and of an oscillatory structure at low fields. By adopting a simple geometrical model we explain the oscillatory structure in terms of electron magnetic focusing. A detailed examination of the zero-field peak lineshape clearly shows deviations from the predictions of ballistic weak localization theory.

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G. Scappucci, L. Di Gaspare, F. Evangelisti, E. Giovine, A. Notargiacomo, R. Leoni, V. Piazza, P. Pingue, F. Beltram. 2004-11-16. Low field magnetotransport in strained Si/SiGe cavities. https://doi.org/10.1103/physrevb.71.245311

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